In the cardiovascular area, intractable cardiovascular disease, such as advanced heart failure, is one of the three major national diseases of Japan. In Japan, which faces an aging society unparalleled in the world, the number of patients suffering from advanced heart failure or a severe aneurysm and the medical cost therefore will increase in the future.
A radical therapy for such intractable cardiovascular diseases has not been established and thus it is assumed that the high medical cost will further increase unless this situation is resolved.
Advanced heart failure is the last stronghold in the area of heart diseases. Currently, about twenty two million people suffer from heart failure around the world, and in the United States of America where heart diseases are the top national cause of death, there are approximately 5.7 million patients with 670,000 people newly developing heart failure every year. The cost required for the treatment is said to reach 37.2 billion dollars per year, leading to the increase in the medical cost. Also, among these patients, the number of advanced heart failure patients who are not expected to improve due to treatment using a pharmaceutical agent is assumed to be approximately 100,000 people (the assumed number worldwide is approximately 200,000). In the United States of America, approximately 2,200 heart transplantations are performed per year.
On the other hand, in Japan, the number of operations for ischemic heart diseases among cardiovascular operations performed in the whole country in 2008 was 19,237. With the most standard isolated coronary artery bypass graft (CABG) operation in ischemic heart disease surgery, primary/elective CABG was performed on 14,943 patients and primary/emergent CABG was performed on 2,508 patients (Non-Patent Document 1).
Development/commercialization and industrialization of medical treatment for advanced heart failure have spread worldwide. In order to deal with the increasing number of patients every year, the establishment of a fundamental treatment for advanced heart failure is urgently needed in Japan where there is feeling of despair in a transplantation therapy due to the significantly insufficient number of donors. Also, a cardiovascular/myocardial regenerative remedy that is an alternative to heart transplantation or artificial hearts, and aims for not relying on artificial hearts is predicted to have a large market scale.
In such circumstances, it is conceivable that a regenerative therapy will be a treatment tool having a high potential to advance the treatment for intractable cardiovascular diseases, and will be an industry that leads to huge economic outcomes. Research on tissue transplantation in which cells are assembled into a tissue for transplantation has been conducted in western countries as well as Japan, and efforts are underway for not only tissue regeneration but also organ regeneration. Research for attempting myocardial tissue regeneration using a tissue engineering method by which cells are seeded in a bioabsorbable support, similarly to bones/cartilages, have mainly been conducted worldwide, but a myocardial tissue having a high cell density has not yet been regenerated.
On the other hand, regeneration of myocardial tissues having a high cell density has been realized, using a tissue regeneration technique in which a unique self-myoblast sheet is used, and the effects on improving heart function have been confirmed by transplantation thereof in the preclinical test, leading to the clinical trial (Non-Patent Document 2).
However, even with such a current tissue regeneration technique, myocardial tissue regeneration that can be an alternative to heart transplantation and completely reverse heart dysfunction in addition to achieving emergency use and universal use has not been achieved.
Also, regarding artificial organs/devices that deal with intractable cardiovascular diseases, even though the functionality is improved, biocompatibility is not sufficient yet, and thus technical breakthrough in eternal use has not been achieved. In order to develop a cardiovascular treatment device having further universality hereafter, it is conceivable that establishing a foundation of medical and engineering fields collaborating in a hybrid type industry by integrating bio/regenerative therapy technology into conventional material/device technology as the basic technology is essential in terms of medical industry development and social importance.